The Environmental Protection Agency (EPA) requires vehicle manufacturers to install on-board diagnostics (OBD) for emission control on the automobiles. OBD systems (e.g., computer, microcontrollers, and sensors) monitor the vehicle's emission on control systems to detect if the emission exceeds EPA-mandated limits. Such a system, for example, employs an oxygen or nitrogen-sensitive sensor located in the vehicle's exhaust manifold and tailpipe.
The EPA requires that all information monitored or calculated by OBD system to be available through a standardized serial 16-pin connector referred to as the ALDL (Assembly Line Diagnostic Link) or OBD connector. The EPA also mandates that, when emission thresholds are exceeded, diagnostic information collected by OBD systems must be stored in the vehicle's central computer so that it can be used during diagnostics and repair.
A second generation of OBD system, called OBD-II system, monitor emission performance and a wide range of additional data that indicate the performance of the host vehicle. For example, in addition to emission, an OBD-II system monitors vehicle speed, mileage, engine temperature, and intake manifold pressure. The OBD-II system also queries manufacturer-specific data, such as engine-performance tuning parameters, alarm status, and properties related to entertainment systems. In total, OBD-II system typically access hundreds of segments of data related to the performance of the vehicle.
With enhancement of standard for the automobile exhaust emission, more attention is paid to the regular exhaust emission inspection rules and systems. The automobile exhaust emission test center can provide an accurate evaluation of the exhaust emission performance, but the cost for this process is high and also it is not practicable for all the vehicles to drive to the exhaust emission test center to have the exhaust emission evaluation test.
Therefore, it is needed a wireless exhaust emission inspection system that is able to automatically inspect exhaust emission data for the automobile vehicles and wirelessly register the exhaust emission data with a test center for further diagnosis, and it is to such system the present invention is primarily directed.